1. Field of the Invention
The invention relates to an arrangement in connection with a current take-off device of a contact rail system, comprising an adapter portion arranged to be connected to be removable electrically and mechanically to a contact rail, and conductors arranged inside the adapter portion and connected by means of slit edge connectors to contacts providing an electric connection for the adapter portion and the contact rail, by means of which conductors the current is conveyed from the adapter portion to an electrical apparatus to be connected thereto.
2. Related Art
Such contact rail systems are nowadays used generally in various rooms for connecting lights, small devices and other such apparatuses by means of a current take-off device to an electric power supply. Various types of current take-off devices and contact rails have been developed. The solutions disclosed in Finnish Patents 84,305 and 92,635 can be mentioned as examples of prior art.
A drawback of the prior art has been complicated structures, for example, which has raised manufacturing costs. Costs are also raised by the fact that the connections of conductors passing to a light inside an adapter, that is, the connections by which the conductors to the light are connected to the contact elements by means of which the adapter is electrically connected to a contact rail, have previously been made by a screw connection. The number of parts and difficult installation required by screw connections has raised costs, for which reason slit edge connections are increasingly used in the field. In slit edge connections a conductor is pushed into a slit in the contact element, in which case the edges forming the slit are cut through the insulating layer of the conductor and the contact element will be in contact with a portion of the conductor conducting electricity. Such a slit edge connector is described in German Patent 31 61 731 and German Offenlegungsschrift 44 03 278.
However, there have been problems with slit edge connectors caused by that the edges forming the slit are not always cut completely through the insulating layer of the conductor. Because of the above-mentioned problems, it is not always possible to provide an electric connection without time-consuming and costly checks, dismounting of conductor joints, reconnections and other additional steps. As a result of dismounting taking place when conductor joints are checked, even contact elements may often get damaged, in which case the contact elements and in some cases even the whole adapter has to be replaced. The costs are also raised because of this.